[PATCH v3 04/11] base-files: upgrade: add get_image_dd()

[Philip Prindeville]

Reviewed-By: Philip Prindeville <philipp at redfish-solutions.com>


> On Nov 10, 2020, at 6:45 AM, Yousong Zhou <yszhou4tech at gmail.com> wrote:
> 
> This is mainly to handle stderr message "Broken pipe", "F+P records
> in/out" by common pattern "xcat | dd .."
> 
> Ref: https://bugs.openwrt.org/index.php?do=details&task_id=3140
> Reported-by: Philip Prindeville <philipp at redfish-solutions.com>
> Signed-off-by: Yousong Zhou <yszhou4tech at gmail.com>
> ---
> package/base-files/files/lib/upgrade/common.sh | 11 +++++++++++
> 1 file changed, 11 insertions(+)
> 
> diff --git a/package/base-files/files/lib/upgrade/common.sh b/package/base-files/files/lib/upgrade/common.sh
> index 5eb7b23a83..a5c27dc2fb 100644
> --- a/package/base-files/files/lib/upgrade/common.sh
> +++ b/package/base-files/files/lib/upgrade/common.sh
> @@ -106,6 +106,17 @@ get_image() { # <source> [ <command> ]
> 	$cmd <"$from"
> }
> 
> +get_image_dd() {
> +	local from="$1"; shift
> +
> +	(
> +		exec 3>&2
> +		( exec 3>&2; get_image "$from" 2>&1 1>&3 | grep -v -F ' Broken pipe'     ) 2>&1 1>&3 \
> +			| ( exec 3>&2; dd "$@" 2>&1 1>&3 | grep -v -E ' records (in|out)') 2>&1 1>&3
> +		exec 3>&-
> +	)
> +}
> +
> get_magic_word() {
> 	(get_image "$@" | dd bs=2 count=1 | hexdump -v -n 2 -e '1/1 "%02x"') 2>/dev/null
> }